It is known that a brake pad is a vehicle wheel braking element that is intended to cooperate with a wheel disc brake and comprises: a metallic support, known as a “backplate”, manufactured as a substantially flat plate; a block of friction material, which is molded integral to a first face of the metallic support, possibly together with the interposition of an isolating/damping layer arranged between the block of friction material and the metallic support and known by the term “underlayer;” and a damping element, known by the term “shim,” applied to a second face of the metallic support opposite the first face, and against said “shim” in use either a movable driving element or a fixed reaction surface of a brake caliper acts, designed to push in use the block of friction material against the brake disc.
The metallic support is commonly made of steel and is obtained by fine shearing of a sheet of metal of appropriate thickness.
In order to improve the adhesion between the block of friction material and the metallic support, the first face of the support may be provided with projecting parts or cavities, as provided, for example, in US2004016608A1 or in US2011220441A1.
However, such a solution can be relatively expensive to implement, insofar as it usually introduces at least one more plastic deformation operation into the metallic support manufacturing cycle. It can also be indecisive, insofar as it involves only a relatively small increase in adhesion, an increase that is not, furthermore, always uniform over the entire surface of the brake pad, and in that it introduces asymmetries into the arrangement of the mass of the metallic support that may give rise to an uncontrolled modification of the natural frequencies of resonant vibration thereof, possibly resulting in the generation of noise while in use.
GB2245667 relates to a metallic support for brake pads which has projecting parts on the first face obtained by means of plastic deformation imparted by the side of the second face, thus leaving cavities on the side of the second face; this does not therefore resolve any of the aforementioned problems.